The 6-foot-9, 277-pound Villanueva has a lot on his plate learning a new position -- defensive end -- with the Eagles, but has impressed coach Chip Kelly with his work ethic.

"I've been kind of partially amazed that he could do what he's done," Kelly said recently, per Phillymag.com. "... There was one day here, you can check with him, I think he went from here to an Army training session and went out and had a couple PT tests that he had to pass and actually one of them was a five-mile test. He nailed it and came back and didn't miss a day.

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"He's been just a guy that you see every day just getting a little bit better, getting a little bit better. As I said the other day, a real intriguing prospect but just amazed at everything that Alejandro does to be honest with you."

The Eaglessigned Villanueva in May after he spent the last four years in active military duty. He last played organized football in 2009 at the U.S. Military Academy.

Villanueva's size and versatility -- he played offensive guard and tight end at Army -- offer compelling options for the outside-the-box thinking Kelly.

"For me, it's all uphill and that's the way I have to look -- is just up," Villanueva said last week. "So hopefully this work that I've put in during this offseason will pay dividends in training camp."